1 /*- 2 * Copyright (c) 1989, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. Neither the name of the University nor the names of its contributors 14 * may be used to endorse or promote products derived from this software 15 * without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 */ 29 30 #if 0 31 #ifndef lint 32 static char const copyright[] = 33 "@(#) Copyright (c) 1989, 1993\n\ 34 The Regents of the University of California. All rights reserved.\n"; 35 #endif /* not lint */ 36 37 #ifndef lint 38 static char sccsid[] = "@(#)echo.c 8.1 (Berkeley) 5/31/93"; 39 #endif /* not lint */ 40 #endif 41 #include <sys/cdefs.h> 42 __FBSDID("$FreeBSD$"); 43 44 #include <sys/types.h> 45 #include <sys/uio.h> 46 47 #include <assert.h> 48 #include <capsicum_helpers.h> 49 #include <err.h> 50 #include <errno.h> 51 #include <limits.h> 52 #include <stdlib.h> 53 #include <string.h> 54 #include <unistd.h> 55 56 /* 57 * Report an error and exit. 58 * Use it instead of err(3) to avoid linking-in stdio. 59 */ 60 static __dead2 void 61 errexit(const char *prog, const char *reason) 62 { 63 char *errstr = strerror(errno); 64 write(STDERR_FILENO, prog, strlen(prog)); 65 write(STDERR_FILENO, ": ", 2); 66 write(STDERR_FILENO, reason, strlen(reason)); 67 write(STDERR_FILENO, ": ", 2); 68 write(STDERR_FILENO, errstr, strlen(errstr)); 69 write(STDERR_FILENO, "\n", 1); 70 exit(1); 71 } 72 73 int 74 main(int argc, char *argv[]) 75 { 76 int nflag; /* if not set, output a trailing newline. */ 77 int veclen; /* number of writev arguments. */ 78 struct iovec *iov, *vp; /* Elements to write, current element. */ 79 char space[] = " "; 80 char newline[] = "\n"; 81 char *progname = argv[0]; 82 83 if (caph_limit_stdio() < 0 || (cap_enter() < 0 && errno != ENOSYS)) 84 err(1, "capsicum"); 85 86 /* This utility may NOT do getopt(3) option parsing. */ 87 if (*++argv && !strcmp(*argv, "-n")) { 88 ++argv; 89 --argc; 90 nflag = 1; 91 } else 92 nflag = 0; 93 94 veclen = (argc >= 2) ? (argc - 2) * 2 + 1 : 0; 95 96 if ((vp = iov = malloc((veclen + 1) * sizeof(struct iovec))) == NULL) 97 errexit(progname, "malloc"); 98 99 while (argv[0] != NULL) { 100 size_t len; 101 102 len = strlen(argv[0]); 103 104 /* 105 * If the next argument is NULL then this is this 106 * the last argument, therefore we need to check 107 * for a trailing \c. 108 */ 109 if (argv[1] == NULL) { 110 /* is there room for a '\c' and is there one? */ 111 if (len >= 2 && 112 argv[0][len - 2] == '\\' && 113 argv[0][len - 1] == 'c') { 114 /* chop it and set the no-newline flag. */ 115 len -= 2; 116 nflag = 1; 117 } 118 } 119 vp->iov_base = *argv; 120 vp++->iov_len = len; 121 if (*++argv) { 122 vp->iov_base = space; 123 vp++->iov_len = 1; 124 } 125 } 126 if (!nflag) { 127 veclen++; 128 vp->iov_base = newline; 129 vp++->iov_len = 1; 130 } 131 /* assert(veclen == (vp - iov)); */ 132 while (veclen) { 133 int nwrite; 134 135 nwrite = (veclen > IOV_MAX) ? IOV_MAX : veclen; 136 if (writev(STDOUT_FILENO, iov, nwrite) == -1) 137 errexit(progname, "write"); 138 iov += nwrite; 139 veclen -= nwrite; 140 } 141 return 0; 142 } 143